The University of Wisconsin Waisman Center on Mental Retardation and Human Development is engaged in biomedical and behavioral research. The biomedical research is in the areas of: Neurochemistry, Neuroendocrinology, and Neurophysiology. Neurochemistry studies include investigations of proteins of the synopse, regulation of cyclic nucleotide metabolism in metabolic diseases and developing brain, the molecular pathology of phenylketonuria and the chemical determinants of aggressive behavior. Neuroendocrinological studies aim to obtain a better understanding of the interactions of hormonal and nervous mechanisms, especially those contributing to control of development of the brain and the neuroendocrine system. Neurophysiology studies include: audition; vision; hypothalamic anatomy; preparation of an atlas of the thalamus and forebrain of the cat. The behavioral research is in the areas of communication, intellectual development, socialization, treatment processes, and infant development. Communication studies include: speech perception and production; the function of the peripheral auditory mechanisms; and language comprehension and its relation to treatment of language disorders. Intellectual development studies include: visual processes, the organization of information input, family-infant interactions and perceptions conditioning; and information processing. Studies in the treatment processes include: family rehabilitation; applied behavioral analysis and modification, and classroom management of severely developmentally disabled. Infant development is engaged in a program of study of infants born after perinatal medical difficulties, who are at risk for central nervous system dysfunction.